Structural elements

ABSTRACT

Compressive and tensile structural elements are disclosed having an enclosure with walls surrounding a cavity. A non-compressible material is disposed in the cavity. The walls are shaped such that a force tending to compress or elongate the element by a first deflection causes an amplified second deflection of the walls into the non-compressible material. The second deflection exerts a compressive force against the non-compressible material, resulting in a resistance to the first deflection and the force tending to compress or elongate the structural element. The walls of the elements are configured for optimum rigidity and/or optimum damping. Structural beams and motion impartation devices utilizing the structural elements to provide lightweight rigidity and/or damping are also disclosed. Another aspect of the present invention are methods of fabricating the structural beams.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The field of art to which this invention relates is structuralelements, and more particularly to lightweight structural elementshaving a cavity in which a non-compressible material is disposedresulting in a rigid structure and/or one capable of vibration damping.

[0003] 2. Description of the Related Art

[0004] It is highly desirable to build high speed machinery which arevery accurate with structural elements that are light weight, have ahigh degree of stiffness, and have high internal dampingcharacteristics. This is in fact the case for any product that issubjected to internally and/or externally induced vibrationalexcitation. With such structural elements, one can then design machines,structures, and other similar devices that are very accurate, that arelighter, and that can operate at higher speeds. This leads to asignificant increase in performance.

[0005] In the prior art, when vibration becomes a factor, designers hadthe option of either adding various combinations of mass andviscoelastic material to the structure to employ a passive damper oremploy some type of active damping device, such as a piezoelectricdevice. While the prior art passive damping devices have theiradvantages, they suffer from the disadvantage of greatly increasing theweight of the structure. This results in a reduction in the attainablespeed of the machine or device. Active dampers, on the other hand, areusually lighter but greatly increase the cost of the machine as well asthe cost of its operation.

[0006] For the above reasons, there is a need in the art for a lowweight, low cost structural element that is very rigid and has highinternal damping.

SUMMARY OF THE INVENTION

[0007] Therefore, it is an object of the present invention to provide alight weight structural element.

[0008] It is a further object of the present invention to provide a lowcost structural element.

[0009] It is yet a further object of the present invention to provide alight weight structural element that provides for increased rigidityover comparable weight structural elements.

[0010] It is still yet a further object of the present invention toprovide a structural element that is light weight and has high internaldamping.

[0011] Accordingly, structural elements are disclosed, wherein a firstembodiment has an enclosure having walls surrounding a cavity, and anon-compressible material disposed in the cavity. The walls are shapedsuch that a force tending to compress the element by a first deflectioncauses an amplified second deflection of the walls into thenon-compressible material. The second deflection exerts a compressiveforce against the non-compressible material, resulting in a resistanceto the first deflection and the force tending to compress the element.

[0012] In a second embodiment, the structural element has an enclosurehaving walls surrounding a cavity, and a non-compressible materialdisposed in the cavity. The walls are shaped such that a force tendingto elongate the element by a first deflection causes an amplified seconddeflection of the walls into the non-compressible material. The seconddeflection exerts a compressive force against the non-compressiblematerial, resulting in a resistance to the first deflection and theforce tending to elongate the element.

[0013] In a third embodiment, the structural elements of the first andsecond embodiments are combined where a first enclosure having firstwalls surrounding a first cavity is provided. A second enclosure havingsecond walls surrounding a second cavity is also provided. Thestructural element further has a first non-compressible materialdisposed in the first cavity, and a second non-compressible materialdisposed in the second cavity. The first walls are shaped such that afirst force tending to compress the element by a first deflection causesan amplified second deflection of the first walls into the firstnon-compressible material, exerting a first compressive force againstthe first non-compressible material, resulting in a resistance to thefirst deflection and the first force tending to compress the element.The second walls are shaped such that a second force tending to elongatethe element by a third deflection causes an amplified fourth deflectionof the second walls into the second non-compressible material, exertinga second compressive force against the second non-compressible material,resulting in a resistance to the third deflection and the second forcetending to elongate the element.

[0014] In a fourth embodiment of the present invention the structuralelement of the first embodiment is configured into a cylindricalenclosure having a wall, a top, a bottom, and a cavity defined by thewall, top and bottom, the top and bottom being separated by a height.The structural element further having a non-compressible materialdisposed in the cavity. The wall is concavely shaped such that a firstcompressive force tending to decrease the height causes an amplifieddeflection of the wall into the non-compressible material, exerting asecond compressive force against the non-compressible material,resulting in a resistance to the amplified deflection and the firstcompressive force.

[0015] In a fifth embodiment of the present invention the structuralelement of the second embodiment is configured similarly to the fourthembodiment except that the wall is convexly shaped such that a tensileforce tending to increase the height of the structural element causes anamplified deflection of the wall into the non-compressible material,exerting a compressive force against the non-compressible material,resulting in a resistance to the amplified deflection and the tensileforce.

[0016] In variations of the fourth and fifth embodiments, the wallcomprises a plurality of panels, the panels being separated by aflectural joint for aiding the deflection of the wall into thenon-compressible material.

[0017] In variations of the above embodiments, the structural elementsare configured for either optimum damping or optimum rigidity or acombination of rigidity and damping.

[0018] In yet other variations of the above embodiments, the structuralelements are disposed on, or in, structural beams configured for eitheroptimum damping, optimum rigidity, or a combination of rigidity anddamping.

[0019] In yet other variations of the above embodiments, the structuralelements are disposed on, or in, motion impartation devices configuredfor either optimum damping, optimum rigidity, or a combination ofrigidity and damping.

[0020] Another aspect of the present invention are methods offabricating the structural beam embodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] These and other features, aspects, and advantages of theapparatus and methods of the present invention will become betterunderstood with regard to the following description, appended claims,and accompanying drawings where:

[0022]FIG. 1A illustrates a front view of a first embodiment of thepresent invention;

[0023]FIG. 1B illustrates a side view of the embodiment of FIG. 1A;

[0024]FIG. 1C illustrates a sectional view of the embodiment of FIG. 1Btaken along line 1C-1C;

[0025]FIG. 2A illustrates a front view of a second embodiment of thepresent invention;

[0026]FIG. 2B illustrates a side view of the embodiment of FIG. 2A;

[0027]FIG. 2C illustrates a sectional view of the embodiment of FIG. 2Btaken along line 2C-2C;

[0028]FIG. 3A illustrates the sectional view of FIG. 1C deflecting undera compressive force;

[0029]FIG. 3B illustrates the sectional view of FIG. 2C deflecting undera tensile force;

[0030]FIG. 4A illustrates a front view of a third embodiment of thepresent invention;

[0031]FIG. 4B illustrates a side view of the embodiment of FIG. 4A;

[0032]FIG. 4C illustrates a sectional view of the embodiment of FIG. 4Btaken along line 4C-4C;

[0033]FIG. 5A illustrates the sectional view of FIG. 4C deflecting undera compressive force;

[0034]FIG. 5B illustrates the sectional view of FIG. 4C deflecting undera tensile force;

[0035]FIGS. 6A, 6B, and 6C illustrate versions of the first threeembodiments, respectively, having a non-uniform wall thickness;

[0036]FIG. 7A illustrates a front view of a fourth embodiment of thepresent invention;

[0037]FIG. 7B illustrates a sectional view of the embodiment of FIG. 7Ataken along line 7B-7B;

[0038]FIG. 7C illustrates a sectional view of the embodiment of FIG. 7Ataken along line 7C-7C;

[0039]FIG. 8A illustrates a front view of a fifth embodiment of thepresent invention;

[0040]FIG. 8B illustrates a sectional view of the embodiment of FIG. 8Ataken along line 8B-8B;

[0041]FIG. 8C illustrates a sectional view of the embodiment of FIG. 8Ataken along line 8C-8C;

[0042]FIG. 9A illustrates an isometric view of a structural beam whereinstructural elements of the first and second embodiments are disposedalong its upper and lower surfaces;

[0043]FIG. 9B illustrates a partial view of FIG. 9A as viewed along line9B-9B;

[0044]FIG. 9C illustrates a partial view of FIG. 9A as viewed along line9C-9C:

[0045]FIG. 10A illustrates an isometric view of a structural beamwherein structural elements of the third embodiment are disposed alongits upper and lower surfaces;

[0046]FIG. 10B illustrates a partial view of FIG. 10A as viewed alongline 10B-10B;

[0047]FIG. 10C illustrates a partial view of FIG. 10A as viewed alongline 10C-10C:

[0048]FIG. 11A illustrates a front view of a sixth embodiment of thepresent invention;

[0049]FIG. 11B illustrates a sectional view of the embodiment of FIG.11A taken along line 11B-11B;

[0050]FIG. 12A illustrates a front view of a structural beam whereinstructural elements of the fourth and fifth embodiments of the presentinvention are disposed throughout the beam's cross-sectional profile;

[0051]FIG. 12B illustrates a sectional view of the beam of FIG. 12Ataken along line 12B-12B;

[0052]FIG. 13A illustrates a front view of a structural beam whereinstructural elements combining the fourth and fifth embodiments of thepresent invention are disposed throughout the beam's cross-sectionalprofile;

[0053]FIG. 13B illustrates a sectional view of the beam of FIG. 13Ataken along line 13B-13B;

[0054]FIG. 14A illustrates a front view of a motion impartation couplingcomprising structural elements of the present invention;

[0055]FIG. 14B illustrates a sectional view of the motion impartationcoupling of FIG. 14A taken along line 14B-14B;

[0056]FIG. 15 illustrates a sectional view of a translating motionimpartation device comprising structural elements of the presentinvention;

[0057]FIG. 16 illustrates a flow diagram outlining the steps forfabricating the structural beam of FIGS. 12A and 12B; and

[0058]FIG. 17 illustrates a flow diagram outlining the steps forfabricating the structural beam of FIGS. 13A and 13B.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0059] Referring now to FIGS. 1A, 1B, 1C, and 3A, there is illustrated afirst embodiment of the present invention, namely, a compressivestructural element referred to generally by reference numeral 100. Thecompressive structural element 100 has an enclosure 102 having walls103, 104 and defining a cavity 106. Walls 104 are preferably formed byextruding the structural element's cross-sectional profile 105, as shownin FIG. 1C. Walls 103 are preferably plates, formed by conventionalmethods, such as stamping, and fastened to the cross-sectional profileby conventional methods, such as welding. However, walls 103 and 104 canbe an integral piece forming the enclosure 102.

[0060] Disposed in the cavity 106 is a non-compressible material 108.The non-compressible material is preferably an elastomer, a liquid or acombination of elastomer and liquid. The non-compressible material, ifan elastomer, is preferably disposed in a length of extrusion having thecross-sectional profile 105 where individual compressive structuralelements 100 are sliced from the extrusion as a predetermined thickness.

[0061] The walls 104 are shaped such that a first compressive force 110,shown in FIG. 3A, tends to compress the structural element 100 by afirst deflection 112 which causes an amplified second deflection 114 ofthe walls 104 into the non-compressible material 108. The relaxedposition of the compressive structural element 100 (i.e., where nocompressive force 110 is present) is shown in FIG. 3A as dashed lines.The walls 104 thereupon exert a second compressive force 116 against thenon-compressible material 108 disposed in the cavity 106. Beingnon-compressible, the non-compressible material 108, resists the secondcompressive force with a resistive force 118 resulting in a resistanceto the first deflection 112 and the first compressive force 110.

[0062] In order to optimize the amplification of the second deflection114, the walls are preferably concavely shaped 120 into the cavity 106.Furthermore, the walls can be configured to provide optimum damping,optimum rigidity, or a combination of the two depending upon theapplication. For instance, as shown in FIGS. 1C and 3A, the walls 104can be of uniform thickness where the end portions 104 a are ofsubstantially the same thickness as the center portion 104 b. Thisconfiguration causes minimal migration of the non-compressible material108 due to the second compressive force 116 resulting in a compressivestructural element 100 which provides for some damping and highrigidity.

[0063] Alternatively, as shown in FIG. 6A, the walls 104 can beconfigured such that the center portion 104 d is substantially thickerthan at the end portions 104 c. This configuration results in increasedmigration of the non-compressible material 108 due to the secondcompressive force 116 resulting in a compressive structural element 100which provides some rigidity and high damping. It is appreciated bysomeone skilled in the art that the wall configuration can be varied toproduce differing degrees of desired damping and rigidity based upon therequirements of the application at hand.

[0064] It is also appreciated by someone skilled in the art thatdifferent non-compressible materials, or combinations ofnon-compressible materials will produce differing degrees of desireddamping and rigidity based upon the requirements of the application athand. For instance, a hard elastomer will produce a more rigidstructural element 100 with little damping, while a softer elastomerwill produce a less rigid structural element 100 with higher damping.Combining an elastomer with a liquid will result in still otherpossibilities regarding damping and rigidity.

[0065] Referring now to FIGS. 2A, 2B, 2C, and 3B, there is illustrated asecond embodiment of the present invention, namely, a tensile structuralelement referred to generally as reference numeral 200 and being similarto the compressive structural element 100 except for the element'sloading and wall configuration to provide damping and rigidity inresponse to the loading. The tensile structural element 200 has anenclosure 202 having walls 203, 204 and defining a cavity 206. Walls 204are again preferably formed by extruding the structural element'scross-sectional profile 205, as shown in FIG. 2C. Walls 203 arepreferably plates, formed by conventional methods, such as stamping, andfastened to the cross-sectional profile by conventional methods, such asspot welding. However, walls 203, 204 can be An integral piece formingthe enclosure 202.

[0066] Disposed in the cavity 206 is a non-compressible material 208. Aswith the compressive structural element 100, the non-compressiblematerial 208 of the tensile compressive element 200 is preferably anelastomer, a liquid or a combination of elastomer and liquid. The walls204 are shaped such that a tensile force 110, shown in FIG. 3B, tends toelongate the structural element 200 by a first deflection 212 whichcauses an amplified second deflection 214 of the walls 204 into thenon-compressible material 208. The relaxed position of the tensilestructural element 200 (i.e., where no tensile force is present) isshown in FIG. 3B as dashed lines. The walls 204 thereupon exert acompressive force 216 against the non-compressible material 208 disposedin the cavity 206. Being non-compressible, the non-compressible material208, resists the compressive force 216 with a resistive force 218resulting in a resistance to the first deflection 212 and the tensileforce 210.

[0067] In order to optimize the amplification of the second deflection214, the walls are preferably convexly shaped 220 away from the cavity206. As discussed previously with regard to the compressive structuralelement 100, the walls 204 can be configured to provide optimum damping,optimum rigidity, or a combination of the two depending upon theapplication. For instance, as shown in FIGS. 2C and 3B, the walls 204can be of uniform thickness where the end portions 204 a art ofsubstantially the same thickness as the center portion 204 b. Asdiscussed previously, this configuration provides for some damping andhigh rigidity.

[0068] Alternatively, as shown in FIG. 6B, the walls 204 can beconfigured such that the center portion 204 d is substantially thickerthan at the end portions 204 c. This configuration results in somerigidity and high damping. As discussed above, it is appreciated bysomeone skilled in the art that the wall configuration can be varied toproduce differing degrees of desired damping and rigidity based upon therequirements of the application at hand.

[0069] As also discussed above, it is also appreciated by someoneskilled in the art that different non-compressible materials, orcombinations of non-compressible materials will also produce differingdegrees of desired damping and rigidity based upon the requirements ofthe application at hand.

[0070] In a third embodiment of the present invention, shown in FIGS.4A, 4B, 4C, 5A, and 5B, the structural elements of the first and secondembodiments are combined resulting in structural element 400. Thestructural element 400 has a compressive and a tensile structuralelement 100, 200, respectively. The compressive structural element 100has a first enclosure 402 having first walls 403, 404, and 405 anddefining a first cavity 406. The tensile structural element 200 has asecond enclosure 502 having second walls 403, 504, and 405 and defininga second cavity 506.

[0071] The first and second walls 404, 504, and 405 are preferablyintegrally formed by extruding the structural element's cross-sectionalprofile 505, as shown in FIG. 4C. First and second walls 403 are alsopreferably integrally formed as plates, by conventional methods, such asstamping, and fastened to the cross-sectional profile by conventionalmethods, such as welding.

[0072] Disposed in the first and second cavities 406, 506 arenon-compressible materials 408, 508. The non-compressible materials arepreferably an elastomer, a liquid or a combination of elastomer andliquid. The first walls 404, 405 are shaped such that a first force 410,shown in FIG. 5A, tending to compress the structural element 400 by afirst deflection 412 causes an amplified second deflection 414 of thefirst walls 404, 405 into the first non-compressible material 408. Thefirst walls 404, 405 thereupon exert a first compressive force 416against the first non-compressible material 408 disposed in the firstcavity 406. Being non-compressible, the first non-compressible material408, resists the first compressive force 416 with a resistive force 418resulting in a resistance to the first deflection 412 and the firstforce 410.

[0073] The second walls 504, 405 are shaped such that a second force510, shown in FIG. 5B, tending to elongate the structural element 400 bya third deflection 512 causes an amplified fourth deflection 514 of thesecond walls 504, 405 into the second non-compressible material 508. Thesecond walls 504, 405 thereupon exert a second compressive force 516against the second non-compressible material 508 disposed in the secondcavity 506. Being non-compressible, the second non-compressible material508, resists the second compressive force 516 with a resistive force 518resulting in a resistance to the third deflection 512 and the secondforce 510.

[0074] Therefore, while in compression due to the first force 410 thestructural element 400 acts as does the compressive structural element100. While in tension due to the second force 510, the structuralelement 400 acts as does the tensile structural element 200.

[0075] In order to optimize the amplification of the second deflection414, the first walls are preferably concavely shaped 420 into the firstcavity 406. Similarly, in order to optimize the amplification of thefourth deflection 514, the second walls are preferably convexly shaped520 away from the second cavity 506. In the preferred configurationshown in FIG. 4C one of the first walls surrounding the first cavity 406also comprises one of the second walls surrounding the second cavity 506resulting in a shared wall 405.

[0076] Furthermore, as discussed above with regard to the compressiveand tensile structural elements 100, 200 the walls and non-compressivematerials can be configured to provide optimum damping, optimumrigidity, or a combination of the two depending upon the application.However, the combined structural element 400 can be configured fordiffering characteristics for resistance to tensile forces andcompressive forces. For instance, the structural element can beconfigured to provide optimum rigidity and low damping in response to acompressive force, and high damping and low rigidity in response to atensile force.

[0077] Configuration of the structural element 400 is achieved asdiscussed above by providing uniform wall thickness 404 a, 404 b, 504 a,504 b, as shown in FIG. 4C, by providing varying wall thickness 404 c,404 d, 504 c, 504 d, as shown in FIG. 6C, and/or by varying the types ofnon-compressible materials as well as their characteristics.

[0078] Referring now to FIGS. 7A, 7B, and 7C there is shown a fourthembodiment of the present invention generally referred to as referencenumeral 700 which is similar to the compressive structural element 100except that the compressive structural element 700 is cylindrical inshape. The compressive structural element 700 has a cylindricalenclosure 702 having a wall 704, a top 706, a bottom 708 and a cavity710 defined by the wall 704, top 706, and bottom 708. The top 706 andbottom 708 of the compressive structural element 700 are separated by aheight 712. The compressive structural element 700 also having anon-compressible material 714 disposed in the cavity 710.

[0079] The wall 704 preferably comprises a plurality of panels 720separated by flectural joints 718 for aiding the deflection of the wall704 into the cavity 710. The flectural joints are preferably “in-turned”portions running longitudinally to the structural elements height. Also,the wall 704, top 706, and bottom 708 preferably comprise an integralmetal shell 722. However, it is appreciated by someone skilled in theart that any suitable material can be utilized without departing fromthe scope and spirit of the invention.

[0080] The operation of compressive element 700 in response to a firstcompressive force will now be explained with reference to FIG. 3A inwhich the cross-sectional profile shown for compressive structuralelement 100 is similar to that of compressive structural element 700,the operation of both therefore being the same. The wall 704 ofcompressive element 700 are concavely shaped 716 such that a firstcompressive force tending to decrease the height 712 causes an amplifieddeflection of the wall 704 into the non-compressible material 714. As aresult, the wall. 704 exerts a second compressive force against thenon-compressible material 714, resulting in a resistance to theamplified deflection and the first compressive force.

[0081] As discussed previously, the non-compressible material ispreferably an elastomer, a liquid, or a combination of elastomer andliquid. Like compressive element 100, compressive element 700 can beconfigured with a wall 704 for either optimum damping, optimum rigidityor any combination of the two. This is achieved as discussed previouslyby providing uniform wall thickness 704 a, 704 b, varying wall thickness(as similarly shown in FIG. 6A), and by varying the type andcharacteristics of the non-compressible material 714.

[0082] Referring now to FIGS. 8A, 8B, and 8C there is shown a fifthembodiment of the present invention generally referred to as referencenumeral 800 which is similar to tensile structural element 200 exceptthat compressive structural element 800 is cylindrical in shape.Compressive structural element 800 has a cylindrical enclosure 802having a wall 804, a top 806, a bottom 808 and a cavity 810 defined bythe wall 804, top 806, and bottom 808. The top 806 and bottom 808 of thecompressive structural element 800 being separated by a height 812. Thetensile structural element 800 also having a non-compressible material814 disposed in the cavity 810.

[0083] The wall 804 preferably comprises a plurality of panels 820separated by flectural joints 818 for aiding the deflection of the wall804 into the cavity 810. The flectural joints are preferably“in-turned”portions running longitudinally to the structural element's height 812.Also, the wall 804, top 806, and bottom 808 preferably comprise anintegral metal shell 822. However, it is appreciated by someone skilledin the art that any suitable material can be utilized without departingfrom the scope and spirit of the invention.

[0084] The operation of compressive element 800 in response to a tensileforce will now be explained with reference to FIG. 3B in which thecross-sectional profile shown for tensile structural element 200 issimilar to that of tensile structural element 800, the operation of boththerefore being the same. The wall 804 of compressive element 800 isconvexly shaped 816 such that a tensile force tending to increase theheight 812 causes an amplified deflection of the wall 804 into thenon-compressible material 814. As a result, the wall 804 exerts acompressive force against the non-compressible material 814, resultingin a resistance to the amplified deflection and the tensile force.

[0085] As discussed previously, the non-compressible material ispreferably an elastomer, a liquid, or a combination of elastomer andliquid. Like tensile element 200, tensile element 800 can be configuredwith a wall 804 for either optimum damping, optimum rigidity or anycombination of the two. This is achieved as discussed previously byproviding uniform wall thickness 804 a, 804 b, varying wall thickness(as similarly shown in FIG. 6B), and by varying the type andcharacteristics of the non-compressible material 814.

[0086] Embodiments of the present invention which utilize the tensileand compressive structural elements 100, 200, and 400 previouslydiscussed will now be described. Referring now to FIGS. 9A, 9B, and 9C,there is illustrated a structural beam generally referred to asreference numeral 900. The structural beam 900 has an upper surface 902in compression and a lower surface 904 in tension due to a loading force906. A web 908 connects the upper surface to the lower surface in atypical I-beam configuration. However, it is appreciated by someoneskilled in the art that beam configurations other than that of an I-beamcan be utilized without departing from the spirit and scope of theinvention.

[0087] A plurality of compressive structural elements 100 are disposedalong the length of the upper surface 902. A plurality of tensilestructural elements 200 are disposed along the length of the lowersurface 904. The structural elements 100, 200 are fastened to theirrespective surfaces 902, 904 by conventional methods. If the enclosuresand beam are metal, the structural elements 100, 200 are preferablywelded. However, any conventional fastening method can be utilized, suchas epoxy bonding or fastening with screws or rivets.

[0088] The compressive structural elements 100 on the upper surface 902and the tensile structural elements 200 on the lower surface 904 provideeither damping or added rigidity to the beam as a result to theirresistance to the loading force 906. As discussed previously, thestructural elements 100, 200 can be configured for optimum damping,rigidity, or any combination thereof.

[0089] Referring now to FIGS. 10A, 10B, and 10C, there is illustrated astructural beam generally referred to as reference numeral 1000. Thestructural beam 1000, like beam 900 has an upper surface 1002 incompression and a lower surface 1004 in tension due to a loading force1006. A web 1008 connects the upper surface to the lower surface in atypical I-beam configuration. However, it is appreciated by someoneskilled in the art that beam configurations other than that of an I-beamcan be utilized without departing from the spirit and scope of theinvention.

[0090] A plurality of combined structural elements 400 are disposedalong the length of the upper and lower surfaces 1002, 1004. Asdiscussed previously, the structural elements 400 are fastened to theupper and lower surfaces 1002, 1004 by conventional methods.

[0091] The combined structural elements 400 on the upper and lowersurfaces 1002, 1004 provide either damping or added rigidity to the beamas a result to their resistance to the loading force 906. As discussedpreviously, the structural elements 100, 200 can be configured foroptimum damping, rigidity, or any combination thereof. However, unlikestructural beam 900, structural beam 1000 is equipped to provide dampingand/or added rigidity to the loading force 1006 in the direction shown,or a loading force in the opposite direction in which the upper surface1002 is in tension and the lower surface 1004 is in compression.Structural beam 1000 therefore being more versatile than structural beam900 which is utilized in situations where the loading force is known notto vary in direction, or where the damping and added rigidity is onlydesired when the loading force is in a certain direction.

[0092] Referring now to FIGS. 11A and 11B there is illustrated a sixthembodiment of the present invention in which a structural beam is shownand generally referred to by reference numeral 1100. The structural beam1100 has an upper surface 1102, a lower surface 1104 and first andsecond walls 1106, 1108, respectively, connecting the upper surface 1102to the lower surface 1104. The volume between the walls 1106, 1108define a cavity 1110 in which a non-compressible material 1112 isdisposed.

[0093] The beams cross-sectional profile, shown in FIG. 11B ispreferably fabricated by an extrusion process. The cavity 1110 ispreferably subsequently filled with non-compressible material 1112 byany method known in the art, such as injecting an elastomer in a liquidstate. As discussed previously, with regard to the other embodiments ofthe present invention the non-compressible material 1112 is preferablyan elastomer, a liquid, or any combination thereof.

[0094] Similar to the compressive element 100, walls 1106, 1108 areshaped such that a first compressive force tending to compress the beam1100 by a first compression causes an amplified second deflection of thewalls 1106, 1108 into the non-compressible material 1112, resulting in aresistance to the first deflection and the force tending to compress thebeam 1100. The force tending to compress the beam 1100 being a loadingforce 1116. Preferably, the beam 1100 has a typical I-Beam configurationwith walls that are concavely shaped 1114 to optimize the deflectioninto the non-compressible material 1112.

[0095] As discussed previously with regard to the previous embodiments,the beam 1100 can be configured for optimum damping, rigidity, or acombination thereof by varying the wall thickness 1108 a, 1108 b and/orby varying the type and characteristics of the non-compressible material1112.

[0096] Embodiments of the present invention which utilize the tensileand compressive structural elements 700 and 800 previously describedwill now be described. Referring now to FIGS. 12A and 12B, there isillustrated a structural beam generally referred to by reference numeral1200. The structural beam having a cross-sectional profile 1202, withfirst portions 1204 of the profile being in compression and secondportions 1206 being in tension due to a loading force 1208. Thestructural beam is preferably configured as an I-Beam having an upperflange 1210 in compression, a lower flange 1212 in tension, and a web1214 connecting the upper flange 1210 to the lower flange 1212. Portionsof-greatest compression 1216 occur in the upper flange 1210, andportions of greatest tension 1218 occur in the lower flange 1212. It isunderstood to someone skilled in the art that the beam can havedifferent cross-sectional profiles and not depart from the scope andspirit of the present invention.

[0097] The beam profile 1202 has a multiplicity of compressivestructural elements 700 disposed in portions of compression 1204.Preferably, the compressive structural elements 700 are of greaterincidence in portions of greatest compression 1216. The beam profile1202 also having a multiplicity of tensile structural elements 800disposed in portions of tension 1206. Preferably, the tensile structuralelements 800 are of greater incidence in portions of greatest tension1218. The compressive and tensile structural elements 700, 800 providedamping and/or rigidity in response to the loading force.

[0098] The structural elements can be configured, as discussedpreviously, for optimum damping, rigidity, or any combination thereof byvarying the wall thickness and/or the type and characteristics of thenon-compressible materials.

[0099] Referring now to FIGS. 13A and 13B there is illustrated astructural beam generally referred to by reference numeral 1300. Thestructural beam having a cross-sectional profile 1302, with firstportions 1304 of the profile being in compression and second portions1306 being in tension due to a loading force 1308. The structural beamis preferably configured as an I-Beam having an upper flange 1310 incompression, a lower flange 1312 in tension, and a web 1314 connectingthe upper flange 1310 to the lower flange 1312. Portions of greatestcompression 1316 occur in the upper flange 1310, and portions ofgreatest tension 1318 occur in the lower flange 1312. It is understoodto someone skilled in the art that the beam can have differentcross-sectional profiles and not depart from the scope and spirit of thepresent invention.

[0100] The beam profile 1302 has a multiplicity of compressive andtensile structural elements 700,800 joined together and disposed inportions of compression and tension 1304 and 1306. Preferably, thejoined structural elements 700,800 are of greater incidence in portionsof greatest compression 1316 and greatest tension 1318.

[0101] The joined structural elements 700,800 can be configured, asdiscussed previously, for optimum damping, rigidity, or any combinationthereof by varying the wall thickness and/or the type andcharacteristics of the non-compressible materials.

[0102] The combined structural elements 700,800 provide either dampingor added rigidity to the beam as a result of their resistance to theloading force 1308. As discussed previously, the structural elements700, 800 can be configured for optimum damping, rigidity, or anycombination thereof. However, unlike structural beam 1200, structuralbeam 1300 is equipped to provide damping and/or added rigidity to theloading force 1308 in the direction shown, or a loading force in theopposite direction in which the upper flange 1310 is in tension and thelower flange 1312 is in compression. Structural beam 1300 thereforebeing more versatile than structural beam 1200 which is utilized insituations where the loading force is known not to vary in direction, orwhere the damping and/or added rigidity is only desired when the loadingforce is in a certain direction.

[0103] Further embodiments of the present invention which utilize thecompressive and tensile structural elements 700,800 previously discussedwill now be described in relation to motion impartation devices.Referring now to FIGS. 14A and 14B, there is illustrated a coupling 1400for imparting rotation (and torque) from a driving shaft 1402 to adriven shaft 1404. The driving shaft 1402 is connected to a drivingportion 1406 of the coupling 1400 and the driven shaft 1404 is connectedto a driven portion 1408 of the coupling 1400.

[0104] The driving portion 1406 is engaged with the driven portion 1408such that a gap 1410 exists between driven and driving portions 1406,1408. Preferably, the driven and driving portions 1406, 1408 comprise aplurality of teeth 1406 a, 1408 a which are meshed together with the gap1410 being between each driving and driven teeth 1406 a, 1408 a,respectively. Disposed in each gap 1410 is a structural element.

[0105] Rotation of the driving portion 1406 results in a compressiveforce being exerted on the driven portion 1408. In the configurationshown in FIG. 14B, where a plurality of driven and driving teeth 1406 a,1408 a are utilized, each driving tooth 1406 a exerts a compressiveforce on the structural element disposed between it and the next driventooth 1408 a in the direction of the rotation. Simultaneously, eachdriven tooth 1408 a exerts a tensile force on the structural elementdisposed between it and the next driving tooth 1406 a in the directionopposite to the direction of rotation. Thus, the structural elementsdisposed in the gaps 1410 provide damping and/or rigidity in response tothe driving rotation (and torque) depending upon the structuralelement's configuration as previously discussed.

[0106] Preferably joined compressive and structural elements 700,800 aredisposed in the gaps 1410 for added versatility, i.e, for the desireddamping and/or rigidity in either direction of rotation. However, allcompressive 700 or all tensile 800 structural elements can be used.However, only half of them would be effectively working in any onedirection of rotation, with the other half working in the oppositedirection of rotation. Another alternative, is to alternate compressive700 and tensile 800 elements in the gaps 1410. However, this arrangementcan only be used if the direction of rotation is known and if it doesnot vary.

[0107] The motion impartation device previously discussed can also beadapted to provide damping and/or rigidity in response to forces exertedwhen imparting translation, or linear motion from a driving portion to adriven portion. Such a device is illustrated in FIG. 15 and generallyreferred to by reference numeral 1500. FIG. 15 illustrates a linearcoupling 1500 for imparting motion from a driving portion 1502 to adriving portion 1504. Like the rotational coupling 1400, the driving anddriven portions 1502, 1504 preferably comprise driven and driving teeth1502 a, 1504 a separated by gaps 1510 in which structural elements aredisposed. The remainder of the linear coupling in principle andstructure is the same as the rotational coupling 1400 previouslydescribed.

[0108] Methods for fabricating the structural beams 1200, 1300previously discussed will now be described. Illustrated in FIG. 16 is aflow chart showing the steps for fabricating structural beam 1200, themethod generally referred to by reference numeral 1600. At step 1610 and1620, respectively, compressive and tensile structural elements 700, 800are provided.

[0109] Preferably the providing steps 1610, 1620 are accomplished byfabricating the first and second non-compressible material to a shapeand size similar to that of the first and second cavities. Thenon-compressible materials can be fabricated by any conventional meansknown in the art, such as injection molding. The first and secondenclosures are then formed around the non-compressible material by anymeans known in the art, preferably by either dipping the elastomers intoa liquid material to form a shell enclosure or by spraying a moltenmaterial onto the non-compressible materials to form a shell. Both ofthese methods require molten shell materials which have a melting pointlower than that of the non-compressible material so that thenon-compressible material is not damaged or melted during the enclosureforming process. In a subsequent operation, flectural joints can becreated by a stamping operation.

[0110] An alternative method for providing 1610, 1620 the compressiveand tensile structural elements 700, 800 comprises forming the first andsecond enclosures and then filling the enclosures with first and secondnon-compressible materials, respectively. The forming of the enclosurescan be done by any means known in the art, such as casting, metalforming, or injection molding. The filling of the enclosures can also bedone by any means known in the art, such as by injecting a liquidmaterial into the enclosure and allowing it to solidify.

[0111] The next step in the fabrication process 1600 is to form thecross-sectional profile of the beam at step 1630. This is accomplishedby conventional processes known in the art, such as by extrusion orcasting. Lastly, at step 1640 the multiplicity of compressive andtensile structural elements 700, 800 are disposed throughout the beamcross-section and along the length of the extrusion. Preferably, thedisposing step 1640 includes the sub-steps of weighting the greatestincidence of compressive structural elements in portions of greatestcompression (step 1640 a) and weighting the greatest incidence oftensile structural elements in portions of greatest tension (at step1640 b).

[0112] The weighing steps 1640 a, 1640 b can be accomplished byproviding a wax, or similar material, extrusion or cast of the beam andpositioning the compressive and tensile structural elements 700, 800within the wax in areas of greatest compression and greatest tension,respectively. The beam is then cast by adding liquid material,preferably metal, to the cast such that the liquid material replaces thewax and the structural elements remain positioned in the portions ofgreatest compression and tension. If the structural elements are denserthan the wax and the wax is sufficiently soft, then the positioning canbe accomplished by inserting the structural elements into the wax andsubjecting the wax beam to a centrifugal force such that the centrifugalforce exerted on the elements causes them to relocate to positions alongthe cross-sectional profile corresponding to portions of greatesttension and compression.

[0113] Alternatively, the weighting steps 1640 a, 1640 b can also beaccomplished by stringing the compressive structural elements 700together along an axis parallel to their walls (i.e., top to bottom),stringing the tensile structural elements 800 together in a similarfashion, positioning the element strings in portions of greatestcompression and greatest tension, and casting or extruding the beamprofile around the element strings such that they remain as positioned.The elements are preferably strung together by wiring the top of anelement to a successive bottom of another element. Alternatively, theelements can be welded together.

[0114] Referring now to FIG. 17, there is illustrated a method forfabricating structural beam 1300 generally referred to by referencenumeral 1700. The method illustrated in FIG. 17 in which all stepssimilar to or identical with those in FIG. 16 are designated with thesame reference numerals, is merely modified with regard to the previousmethod, in that the structural elements 700, 800 are joined at step 1710to form a combined structural element. The joining is preferablyaccomplished by welding the structural elements together to form ashared wall.

[0115] Also, modified with regard to the previous method is theweighting step which only comprises weighting the combined structuralelement throughout the beam profile, instead of weighting eachstructural element as is done in the previous method. The preferablemethods for weighting of the elements and positioning the elements asdiscussed in the previous method are likewise the same.

[0116] From the foregoing, it becomes readily apparent to one skilled inthe art that the novel structural elements of the present inventionoffers increased rigidity and damping over currently employed devices.Due to the inventive structural element configuration, the advantagesoffered by the inventive structure resides in:

[0117] (a) because the walls of the structural elements can be maderelatively thin, and because the non-compressible material is relativelylightweight, the structural element can be made very lightweight;

[0118] (b) because of the novel configuration whereby thenon-compressible material resists any loading forces, the structuralelement can be configured for high rigidity;

[0119] (c) because of the novel configuration, the structural elementcan also provide high internal damping by configuring the walls toprovide for an increased migration of non-compressible material withinthe cavity; and

[0120] (d) because of its lightweight, high rigidity, and high internaldamping characteristics, the structural element of the present inventionprovides a reliable, low cost alternative to active damping devices.

[0121] While there has been shown and described what is considered to bepreferred embodiments of the invention, it will, of course, beunderstood that various modifications and changes in form or detailcould readily be made without departing from the spirit of theinvention. It is therefore intended that the invention be not limited tothe exact forms described and illustrated, but should be constructed tocover all modifications that may fall within the scope of the appendedclaims.

I claim:
 1. A compressive structural element comprising: an enclosurehaving walls surrounding a cavity; and a non-compressible materialdisposed in the cavity; wherein the walls are shaped such that a firstcompressive force tending to compress the element by a first deflectioncauses an amplified second deflection of the walls into thenon-compressible material, exerting a second compressive force againstthe non-compressible material, resulting in a resistance to the firstdeflection and the first compressive force tending to compress theelement.
 2. The compressive structural element of claim 1, wherein thewalls are concavely shaped.
 3. The compressive structural element ofclaim 1, wherein the walls are of a uniform thickness such that thesecond deflection causes minimal migration of the non-compressiblematerial.
 4. The compressive structural element of claim 1, wherein thewalls gradually become thicker at the center of the cavity such that thesecond deflection causes increased migration of the non-compressiblematerial.
 5. The compressive structural element of claim 1, wherein thenon-compressible material is an elastomer.
 6. The compressive structuralelement of claim 1, wherein the non-compressible material is a liquid.7. The compressive structural element of claim 1, wherein thenon-compressible material is a combination of elastomer and liquid.
 8. Atensile structural element comprising: an enclosure having wallssurrounding a cavity; and a non-compressible material disposed in thecavity; wherein the walls are shaped such that a tensile force tendingto elongate the element by a first deflection causes an amplified seconddeflection of the walls into the non-compressible material, exerting acompressive force against the non-compressible material, resulting in aresistance to the first deflection and the tensile force tending toelongate the element.
 9. The tensile structural element of claim 8,wherein the walls are convexly shaped.
 10. The tensile structuralelement of claim 8, wherein the walls are of a uniform thickness suchthat the second deflection causes minimal migration of thenon-compressible material.
 11. The tensile structural element of claim8, wherein the walls gradually become thicker at the center of thecavity such that the second deflection causes increased migration of thenon-compressible material.
 12. The tensile structural element of claim8, wherein the non-compressible material is an elastomer.
 13. Thetensile structural element of claim 8, wherein the non-compressiblematerial is a liquid.
 14. The compressive structural element of claim 8,wherein the non-compressible material is a combination of elastomer andliquid.
 15. A structural element comprising: compressive and tensilestructural elements the compressive structural element having a firstenclosure having first walls surrounding a first cavity; the tensilestructural element having a second enclosure having second wallssurrounding a second cavity; a first non-compressible material disposedin the first cavity; and a second non-compressible material disposed inthe second cavity; wherein the first walls are shaped such that a firstforce tending to compress the structural element by a first deflectioncauses an amplified second deflection of the first walls into the firstnon-compressible material, exerting a first compressive force againstthe first non-compressible material, resulting in a resistance to thefirst deflection and the first force tending to compress the structuralelement; and the second walls are shaped such that a second forcetending to elongate the structural element by a third deflection causesan amplified fourth deflection of the second walls into the secondnon-compressible material, exerting a second compressive force againstthe second non-compressible material, resulting in a resistance to thethird deflection and the second force tending to elongate the structuralelement.
 16. The structural element of claim 15, wherein at least one ofthe first walls surrounding the first cavity also comprises at least oneof the second walls surrounding the second cavity.
 17. The structuralelement of claim 15, wherein the first walls are concavely shaped. 18.The structural element of claim 15, wherein the second walls areconvexly shaped.
 19. The structural element of claim 15, wherein thefirst and second walls are of a uniform thickness such that the secondor fourth deflection causes minimal migration of the first and secondnon-compressible materials, respectively.
 20. The structural element ofclaim 15, wherein the first and second walls gradually become thicker atthe center of the first and second cavities such that the second orfourth deflection causes increased migration of the first and secondnon-compressible materials, respectively.
 21. The structural element ofclaim 15, wherein at least one of the first and second non-compressiblematerials is an elastomer.
 22. The structural element of claim 15,wherein at least one of the first and second non-compressible materialsis a liquid.
 23. The structural element of claim 15, wherein at leastone of the first and second non-compressible materials is a combinationof elastomer and liquid.
 24. A compressive structural elementcomprising; a cylindrical enclosure having a wall, a top, a bottom, anda cavity defined by the wall, top and bottom, the top and bottom beingseparated by a height; and a non-compressible material disposed in thecavity; wherein the walls are concavely shaped such that a firstcompressive force tending to decrease the height causes an amplifieddeflection of the wall into the non-compressible material, exerting asecond compressive force against the non-compressible material,resulting in a resistance to the amplified deflection and the firstcompressive force.
 25. The compressive structural element of claim 24,wherein the wall, top and bottom comprise an integral shell surroundingthe non-compressible material disposed in the cavity.
 26. Thecompressive structural element of claim 25, wherein the wall comprises aplurality of panels separated by flectural joints for aiding thedeflection of the wall into the non-compressible material.
 27. Thecompressive structural element of claim 25, wherein the shell is ametal.
 28. The compressive structural element of claim 24 wherein thewall is of a uniform thickness such that the amplified deflection causesminimal migration of the non-compressible material.
 29. The compressivestructural element of claim 24, wherein the wall gradually becomesthicker at the center of the cavity such that the amplified deflectioncauses increased migration of the non-compressible material.
 30. Thecompressive structural element of claim 24, wherein the non-compressiblematerial is an elastomer.
 31. The compressive structural element ofclaim 24, wherein the non-compressible material is a liquid.
 32. Thecompressive structural element of claim 24, wherein the non-compressiblematerial is a combination of elastomer and liquid.
 33. A tensilestructural element comprising; a cylindrical enclosure having a wall, atop, a bottom, and a cavity defined by the wall, top and bottom, the topand bottom being separated by a height; and a non-compressible materialdisposed in the cavity; wherein the walls are convexly shaped such thata tensile force tending to increase the height causes an amplifieddeflection of the wall into the non-compressible material, exerting acompressive force against the non-compressible material, resulting in aresistance to the amplified deflection and the tensile force.
 34. Thetensile structural element of claim 33, wherein the wall, top and bottomcomprise an integral shell surrounding the non-compressible materialdisposed in the cavity.
 35. The tensile structural element of claim 34,wherein the shell is a metal.
 36. The tensile structural element ofclaim 33, wherein the wall comprises a plurality of panels separated byflectural joints for aiding the deflection of the wall into thenon-compressible material.
 37. The tensile structural element of claim33, wherein the wall is of a uniform thickness such that the amplifieddeflection causes minimal migration of the non-compressible material.38. The tensile structural element of claim 33, wherein the wallgradually becomes thicker at the center of the cavity such that theamplified deflection causes increased migration of the non-compressiblematerial.
 39. The tensile structural element of claim 33, wherein thenon-compressible material is an elastomer.
 40. The tensile structuralelement of claim 33, wherein the non-compressible material is a liquid.41. The compressive structural element of claim 33, wherein thenon-compressible material is a combination of elastomer and liquid. 42.A structural beam comprising; an upper surface in compression due to aloading force; a lower surface in tension due to the loading force;means for connecting the upper and lower surfaces; a plurality ofcompressive structural elements disposed along the length of the uppersurface, each compressive structural element comprising a firstenclosure having first walls surrounding a first cavity, and a firstnon-compressible material disposed in the first cavity, wherein thefirst walls are shaped such that the loading force tends to compress thecompressive structural element by a first deflection causing anamplified second deflection of the first walls into the firstnon-compressible material, exerting a compressive force against thefirst non-compressible material, resulting in a resistance to the firstdeflection and the loading force; and a plurality of tensile structuralelements disposed along the length of the lower surface, each tensilestructural element comprising a second enclosure having second wallssurrounding a second cavity, and a second non-compressible materialdisposed in the second cavity, wherein the second walls are shaped suchthat the loading force tends to elongate the tensile structural elementby a third deflection causing an amplified fourth deflection of thesecond walls into the second non-compressible material, exerting acompressive force against the second non-compressible material,resulting in a resistance to the third deflection and the loading force.43. The structural beam of claim 42, wherein the shape of the beam is anI-beam and the means for connecting the upper and lower surfaces is aweb.
 44. The structural beam of claim 42, wherein the first and secondwalls are of a uniform thickness such that the second and fourthdeflections causes minimal migration of the first and secondnon-compressible materials, respectively.
 45. The structural beam ofclaim 42, wherein the first and second walls gradually become thicker atthe center of the first and second cavities, such that the second andfourth deflections causes increased migration of the first and secondnon-compressible materials, respectively.
 46. The tensile structuralelement of claim 42, wherein at least one of the first and secondnon-compressible materials is an elastomer.
 47. The tensile structuralelement of claim 42, wherein at least one of the first and secondnon-compressible materials is a liquid.
 48. The compressive structuralelement of claim 42, wherein at least one of the first and secondnon-compressible materials is a combination of elastomer and liquid. 49.A structural beam comprising; an upper surface in one of compression ortension due to a loading force; a lower surface in the other ofcompression or tension due to the loading force; means for connectingthe upper surface to the lower surface; and a plurality of structuralelements disposed along the length of the upper and lower surfaces, eachstructural element comprising a compressive and a tensile structuralelement, the compressive structural element having a first enclosurehaving first walls surrounding a first cavity, the tensile structuralelement having a second enclosure having second walls surrounding asecond cavity, a first non-compressible material disposed in the firstcavity, and a second non-compressible material disposed in the secondcavity, wherein the first walls are shaped such that the loading forcetends to compress the structural element by a first deflection causingan amplified second deflection of the first walls into the firstnon-compressible material, exerting a first compressive force againstthe first non-compressible material, resulting in a resistance to thefirst deflection and the loading force, and wherein the second walls areshaped such that the loading force tends to elongate the structuralelement by a third deflection causing an amplified fourth deflection ofthe second walls into the second non-compressible material, exerting asecond compressive force against the second non-compressible material,resulting in a resistance to the third deflection and the loading force.50. The structural beam of claim 49, wherein the shape of the beam is anI-beam and the means for connecting the upper and lower surfaces is aweb.
 51. The structural beam of claim 49, wherein the first and secondwalls are of a uniform thickness such that the second and fourthdeflections causes minimal migration of the first and secondnon-compressible materials, respectively.
 52. The structural beam ofclaim 49, wherein the first and second walls gradually become thicker atthe center of the first and second cavities, such that the second andfourth deflections causes increased migration of the first and secondnon-compressible materials, respectively.
 53. The structural beam ofclaim 49, wherein at least one of the first and second non-compressiblematerials is an elastomer.
 54. The structural beam of claim 49, whereinat least one of the first and second non-compressible materials is aliquid.
 55. The structural beam of claim 49, wherein at least one of thefirst and second non-compressible materials is a combination ofelastomer and liquid.
 56. A structural beam comprising: an uppersurface; a lower surface; a first and second wall connecting the upperand lower surface, the volume between the walls defining a cavity; and anon-compressible material disposed in the cavity; wherein the walls areshaped such that a first compressive force tending to compress the beamby a first deflection causes an amplified second deflection of the wallsinto the non-compressible material, exerting a second compressive forceagainst the non-compressible material, resulting in a resistance to thefirst deflection and the force tending to compress the beam.
 57. Thestructural beam of claim 56, wherein the shape of the beam is an I-beam.58. The structural beam of claim 56, wherein the walls are concavelyshaped.
 59. The structural beam of claim 56, wherein the walls are of auniform thickness such that the second deflection causes minimalmigration of the non-compressible material.
 60. The structural beam ofclaim 56, wherein the walls gradually become thicker at the center ofthe cavity such that the second deflection causes increased migration ofthe non-compressible material.
 61. The tensile structural element ofclaim 56, wherein the non-compressible material is an elastomer.
 62. Thetensile structural element of claim 56, wherein the non-compressiblematerial is a liquid.
 63. The compressive structural element of claim56, wherein the non-compressible material is a combination of elastomerand liquid.
 64. A structural beam having a cross-sectional profile,first portions of the profile being in compression and second portionsof the profile being in tension due to a loading force, the beamcomprising: a multiplicity of compressive structural elements disposedthroughout the cross-sectional profile in the portions in compression,each compressive structural element comprising a first enclosure havingfirst walls surrounding a first cavity, and a first non-compressiblematerial disposed in the first cavity, wherein the first walls areshaped such that the compressive force due to the loading force tends tocompress the compressive structural element by a first deflectioncausing an amplified second deflection of the first walls into the firstnon-compressible material, exerting a compressive force due to thesecond deflection against the first non-compressible material, resultingin a resistance to the first deflection and the loading force; and amultiplicity of tensile structural elements disposed throughout thecross-sectional profile in the portions in tension, each tensile elementcomprising a second enclosure having second walls surrounding a secondcavity, and a second non-compressible material disposed in the secondcavity, wherein the second walls are shaped such that the tensile forcedue to the loading force tends to elongate the tensile structuralelement by a third deflection causing an amplified fourth deflection ofthe second walls into the second non-compressible material, exerting acompressive force due to the fourth deflection against the secondnon-compressible material, resulting in a resistance to the thirddeflection and the loading force.
 65. The structural beam of claim 64,wherein the first structural elements are of greater incidence inportions of greatest compression, and wherein the second structuralelements are of greater incidence in portions of greatest tension. 66.The structural beam of claim 64, wherein the shape of the beam is anI-beam, having an upper flange in compression, a lower flange intension, and a web connecting the upper and lower flanges, and whereinthe portions of greatest compression is in the upper flange, and theportions of greatest tension is in the lower flange.
 67. The structuralbeam of claim 64, wherein the first and second walls are of a uniformthickness such that the second and fourth deflections causes minimalmigration of the first and second non-compressible materials,respectively.
 68. The structural beam of claim 64, wherein the first andsecond walls gradually become thicker at the center of the first andsecond cavities, such that the second and fourth deflections causesincreased migration of the first and second non-compressible materials,respectively.
 69. The tensile structural element of claim 64, wherein atleast one of the first and second non-compressible materials is anelastomer.
 70. The tensile structural element of claim 64, wherein atleast one of the first and second non-compressible materials is aliquid.
 71. The tensile structural element of claim 64, wherein at leastone of the first and second non-compressible materials is a combinationof elastomer and liquid.
 72. A structural beam having a cross-sectionalprofile, first portions of the profile being in compression and secondportions of the profile being in tension due to a loading force, thebeam comprising: a multiplicity of structural elements disposedthroughout the cross-sectional profile of the beam, each structuralelement comprising a compressive and a tensile structural element, thecompressive structural element having a first enclosure having firstwalls surrounding a first cavity, the tensile structural element havinga second enclosure having second walls surrounding a second cavity, afirst non-compressible material disposed in the first cavity, and asecond non-compressible material disposed in the second cavity, whereinthe first walls are shaped such that the loading force tends to compressthe structural element by a first deflection causing an amplified seconddeflection of the first walls into the first non-compressible material,exerting a first compressive force against the first non-compressiblematerial, resulting in a resistance to the first deflection and theloading force, and wherein the second walls are shaped such that theloading force tends to elongate the structural element by a thirddeflection causing an amplified fourth deflection of the second wallsinto the second non-compressible material, exerting a second compressiveforce against the second non-compressible material, resulting in aresistance to the third deflection and the loading force.
 73. Thestructural beam of claim 72, wherein the structural elements are ofgreater incidence in portions of greatest compression and greatestLension.
 74. The structural beam of claim 73, wherein the shape of thebeam is an I-beam, having an upper flange in compression, a lower flangein tension, and a web connecting the upper and lower flanges, andwherein the portions of greatest compression is in the upper flange, andthe portions of greatest tension is in the lower flange.
 75. Thestructural beam of claim 72, wherein the first and second walls are of auniform thickness such that the second and fourth deflections causesminimal migration of the first and second non-compressible materials,respectively.
 76. The structural beam of claim 72, wherein the first andsecond walls gradually become thicker at the center of the first andsecond cavities, such that the second and fourth deflections causesincreased migration of the first and second non-compressible materials,respectively.
 77. The structural beam of claim 72, wherein at least oneof the first and second non-compressible materials is an elastomer. 78.The structural beam of claim 72, wherein at least one of the first andsecond non-compressible materials is a liquid.
 79. The structural beamof claim 72, wherein at least one of the first and secondnon-compressible materials is a combination of elastomer and liquid. 80.A motion impartation device comprising; a driving portion; a drivenportion engaged with the driving portion such that a gap separates thedriving portion from the driven portion; and a structural elementdisposed in each gap such that a first compressive force is transferredfrom the driven portion to the driving portion and a tensile force istransferred from the driven portion to the driving portion, eachstructural element comprising a compressive and a tensile structuralelement, the compressive structural element having a first enclosurehaving first walls surrounding a first cavity, the tensile structuralelement having a second enclosure having second walls surrounding asecond cavity, a first non-compressible material disposed in the firstcavity, and a second non-compressible material disposed in the secondcavity, wherein the first walls are shaped such that the compressionforce tends to compress the compressive structural element by a firstdeflection causing an amplified second deflection of the first wallsinto the first non-compressible material, exerting a second compressiveforce against the first non-compressible material, resulting in aresistance to the first deflection and the first compressive force, andwherein the second walls are shaped such that the tensile force tends toelongate the structural element by a third deflection causing anamplified fourth deflection of the second walls into the secondnon-compressible material, exerting a third compressive force againstthe second non-compressible material, resulting in a resistance to thethird deflection and the tensile force.
 81. The motion impartationdevice of claim 80, wherein the device is a coupling for impartingrotation from a driving shaft to a driven shaft, the driving shaft beingconnected to the driving portion and the driven shaft being connected tothe driven portion, the driving and driven portions each having aplurality of teeth, the teeth being meshingly engaged wherein thestructural elements are disposed in gaps between the teeth of the drivenportion and the teeth of the driving portion.
 82. The motion impartationdevice of claim 80, wherein the device is a coupling for impartingtranslation of the driven portion to the driving portion, the drivingand driven portions each having a plurality of teeth, the teeth beingmeshingly engaged wherein the structural elements are disposed in gapsbetween the teeth of the driven portion and the teeth of the drivingportion.
 83. The motion impartation device of claim 80, wherein thefirst and second walls are of a uniform thickness such that the secondand fourth deflections causes minimal migration of the first and secondnon-compressible materials, respectively.
 84. The motion impartationdevice of claim 80, wherein the first and second walls gradually becomethicker at the center of the first and second cavities, such that thesecond and fourth deflections causes increased migration of the firstand second non-compressible materials, respectively.
 85. The motionimpartation device of claim 80, wherein at least one of the first andsecond non-compressible materials is an elastomer.
 86. The motionimpartation device of claim 80, wherein at least one of the first andsecond non-compressible materials is a liquid.
 87. The motionimpartation device of claim 80, wherein at least one of the first andsecond non-compressible materials is a combination of elastomer andliquid.
 88. A method for fabricating a structural beam having across-sectional profile, first portions of the profile being incompression and second portions of the profile being in tension due to aloading force, the beam also having compressive and tensile structuralelements, each compressive structural element comprising a firstenclosure having first walls surrounding a first cavity, and a firstnon-compressible material disposed in the first cavity, wherein thefirst walls are shaped such that the compressive force due to theloading force tends to compress the compressive structural element by afirst deflection causing an amplified second deflection of the firstwalls into the first non-compressible material, exerting a compressiveforce due to the second deflection against the first non-compressiblematerial, resulting in a resistance to the first deflection and theloading force, and each tensile element comprising a second enclosurehaving second walls surrounding a second cavity, and a secondnon-compressible material disposed in the second cavity, wherein thesecond walls are shaped such that the tensile force due to the loadingforce tends to elongate the tensile structural element by a thirddeflection causing an amplified fourth deflection of the second wallsinto the second non-compressible material, exerting a compressive forcedue to the fourth deflection against the second non-compressiblematerial, resulting in a resistance to the third deflection and theloading force, the method comprising the steps of; providing compressivestructural elements of the present invention; providing tensilestructural elements of the present invention; forming thecross-sectional profile of the beam to a predetermined length; anddisposing a multiplicity of the compressive and tensile structuralelements throughout the beam cross-sectional profile and along itslength.
 89. The method of claim 88, wherein the providing steps furtherinclude the sub-steps of: fabricating the first non-compressiblematerial to a shape and size substantially similar to that of the firstcavity; fabricating the second non-compressible material to a shape andsize substantially similar to that of the second cavity; forming thefirst enclosures having first walls, around the first non-compressiblematerial; and forming the second enclosures having second walls, aroundthe second non-compressible material.
 90. The method of claim 89,wherein the steps of fabricating the first and second non-compressiblematerials are performed by injection molding, wherein thenon-compressible material is an elastomer.
 91. The method of claim 89,wherein the steps of forming the first and second enclosures aroundtheir respective first and second non-compressible materials areperformed by spraying a metal shell onto the first and secondnon-compressible materials.
 92. The method of claim 89, wherein thesteps of forming the first and second enclosures around their respectivefirst and second non-compressible materials are performed by dipping theelastomer into a liquid material bath which hardens to form a shellaround the first and second non-compressible materials.
 93. The methodof claim 88, wherein the providing steps further include the sub-stepsof: forming the first enclosure; forming the second enclosure; fillingthe first enclosure with the first non-compressible material; andfilling the second enclosure with the second non-compressible material.94. The method of claim 88, wherein the step of disposing a multiplicityof the compressive and tensile structural elements throughout the beamcross-sectional profile and along its length further includes thesub-steps of: weighting the greatest incidence of compressive structuralelements in portions of greatest compression; and weighting the greatestincidence of tensile structural elements in portions of greatesttension.
 95. The method of claim 94, wherein the weighting sub-stepscomprise: providing a wax replica of the beam; positioning thecompressive and tensile structural elements within the wax replica inportions of greatest compression and greatest tension, respectively;casting the beam by adding liquid material to the wax replica such thatthe liquid material replaces the wax and the structural elements remainpositioned in the portions of greatest compression and tension.
 96. Themethod of claim 95, wherein the positioning sub-step is performed bysubjecting the wax replica to centrifugal force such that thecentrifugal force exerted on the, compressive and tensile elementscauses them to relocate to positions along the cross-sectional profilecorresponding to portions of greatest compression and portions ofgreatest tension, respectively.
 97. The method of claim 94, wherein theweighting sub-steps comprise: stringing the compressive structuralelements together along an axis parallel to their walls; stringing thetensile structural elements together along an axis parallel to theirwalls; positioning the compressive and tensile structural elementstrings in areas of greatest portions of compression and tension,respectively; and casting the beam around the compressive and tensilestructural element strings such that they remain positioned in areas ofgreatest compression and tension, respectively.
 98. The method of claim97, wherein the stringing sub-step comprises welding the elementstogether.
 99. The method of claim 97, wherein the forming step comprisescasting the beam after the positioning step.
 100. The method of claim97, wherein the forming step comprises extruding the beam, and where theextruding occurs simultaneous with the positioning step.
 101. A methodfor fabricating a structural beam having a cross-sectional profile,first portions of the profile being in compression and second portionsof the profile being in tension due to a loading force, the beam alsohaving structural elements, each structural element comprising acompressive and tensile structural element, the compressive structuralelement having a first enclosure having first walls surrounding a firstcavity, the tensile structural element having a second enclosure havingsecond walls surrounding a second cavity, a first non-compressiblematerial disposed in the first cavity, and a second non-compressiblematerial disposed in the second cavity, wherein the first walls areshaped such that the loading force tends to compress the structuralelement by a first deflection causing an amplified second deflection ofthe first walls into the first non-compressible material, exerting afirst compressive force against the first non-compressible material,resulting in a resistance to the first deflection and the loading force,and wherein the second walls are shaped such that the loading forcetends to elongate the structural element by a third deflection causingan amplified fourth deflection of the second walls into the secondnon-compressible material, exerting a second compressive force againstthe second non-compressible material, resulting in a resistance to thethird deflection and the loading force, the method comprising the stepsof; providing compressive structural elements of the present invention;providing tensile structural elements of the present invention; joiningthe compressive and tensile structural elements to form the structuralelements; forming the cross-sectional profile of the beam to apredetermined length; and disposing a multiplicity of the structuralelements throughout the beam cross-sectional profile and along itslength.
 102. The method of claim 101, wherein the providing stepsfurther include the sub-steps of: fabricating the first non-compressiblematerial to a shape and size substantially similar to that of the firstcavity; fabricating the second non-compressible material to a shape andsize substantially similar to that of the second cavity; forming thefirst enclosure having first walls, around the first non-compressiblematerial; and forming the second enclosure having second walls, aroundthe second non-compressible material.
 103. The method of claim 102,wherein the steps of fabricating the first and second non-compressiblematerials are performed by injection molding, wherein thenon-compressible material is an elastomer.
 104. The method of claim 102,wherein the steps of forming the first and second enclosures aroundtheir respective first and second non-compressible materials areperformed by spraying a metal shell onto the first and secondnon-compressible materials.
 105. The method of claim 102, wherein thesteps of forming the first and second enclosures around their respectivefirst and second non-compressible materials are performed by dipping theelastomer into a liquid material bath which hardens to form a shellaround the first and second non-compressible materials.
 106. The methodof claim 101, wherein the providing steps further include the sub-stepsof: forming the first enclosure; forming the second enclosure; fillingthe first enclosure with the first non-compressible material; andfilling the second enclosure with the second non-compressible material.107. The method of claim 101, wherein the step of disposing amultiplicity of the structural elements throughout the beamcross-sectional profile and along its length further includes thesub-step of weighting the greatest incidence of structural elements inportions of greatest compression and greatest tension.
 108. The methodof claim 107, wherein the weighting sub-steps comprise: providing a waxreplica of the beam; positioning the compressive and tensile structuralelements within the wax replica in portions of greatest compression andgreatest tension, respectively; casting the beam by adding liquidmaterial to the wax replica such that the liquid material replaces thewax and leaves the structural elements in their positions.
 109. Themethod of claim 108, wherein the positioning sub-step is performed bysubjecting the wax replica to centrifugal force such that thecentrifugal force exerted on the compressive and tensile elements causesthem to relocate to positions along the cross-sectional profilecorresponding to portions of greatest compression and portions ofgreatest tension, respectively.
 110. The method of claim 107, whereinthe weighting sub-steps comprise: stringing the compressive structuralelements together along an axis parallel to their walls; stringing thetensile structural elements together along an axis parallel to theirwalls; positioning the compressive and tensile structural elementstrings in areas of greatest portions of compression and tension,respectively; and forming the beam around the compressive and tensilestructural element strings such that they remain in areas of greatestcompression and tension, respectively.
 111. The method of claim 110,wherein the stringing sub-step comprises welding the elements together.112. The method of claim 110, wherein the forming step comprises castingthe beam after the positioning step.
 113. The method of claim 110,wherein the forming step comprises extruding the beam, and where theextruding occurs simultaneous with the positioning step.
 114. The methodof claim 101, wherein the joining step comprises welding the compressiveand tensile structural elements together to form a common wall.